不同鸭种蛋品质的比较

本研究通过测定处于产蛋高峰的5个种鸭群同一天各100枚种蛋的蛋重、蛋形指数、蛋壳强度、蛋壳厚度等4个蛋品质指标,比较了5个种鸭群种蛋的品质。结果表明:5个鸭群种蛋明显可分为三类,祖代番鸭与父母代番鸭种蛋为一类,金定鸭与“苏牧”鸭种蛋为另一类,而SM3樱桃谷鸭种蛋自成一类,每类种蛋的各项指标接近,而与其他类种蛋存在一定差异;从蛋品质各项指标综合分析来看,番鸭种蛋品质最好,而SM3樱桃谷鸭种蛋品质最差,这解释了生产中为什么樱桃谷种蛋破损率比较高的缘故;同时,通过本研究,为进一步提高我场培育的“苏牧”鸭产蛋性能提供了重要的参考依据。     

饲料中添加油脂对肉鸭生产性能的影响

本试验选用1日龄樱桃谷肉鸭500只，随机分为10个组（9个试验组和1个对照组），每组50只肉仔鸭。试验组采用二因素、每个因素三个水平的完全随机设计．即在饲粮中添加3％、6％、和9％的大豆油，每个比例分别添饲1周、2周、3周，旨在研究日粮中添加大豆油的用量和时间对内鸭生产性能的影响。结果表明：各试验组之问以及各试验组与对照组之间肉鸭的死亡率无显著差异（P〉0．05）；各试验组与对照组之间肉鸭的饲料转化率有显著差异（P〈0．05），各试验组之间肉鸭的饲料转化率无显著差异（P〉0．05）；添加大豆油的比例、时期及比例与添饲时的互作对内鸭的日增重均有极显著的影响（P〈0．01）．而以添加6％的比例添饲两周的效果最好。     

鹅填肥饲料中添加动植物性油脂对肥肝性能的影响

鹅肥肝生产饲料中添加植物油脂的肥肝重平均大于动物油脂45g,但差异不显著(P>0.05),二者增重速度、屠宰性能差异不显著(P>0.05)。植物油脂添加组肠、肌腺胃重大于动物油脂组8.39%,这可能与动物油脂容易消化吸收有关。血液生化指标与酶类含量差异不显著。     

鹅填肥饲料中添加动植物性油脂对肥肝性能的影响

鹅肥肝生产饲料中添加植物油脂的肥肝重平均大于动物油脂45g，但差异不显著（P〉0．05），二者增重速度、屠宰性能差异不显著（P〉0．05）。植物油脂添加组肠、肌腺胃重大于动物油脂组8．39％，这可能与动物油脂容易消化吸收有关。血液生化指标与酶类含量差异不显著。     

日粮中添加柠檬酸对蛋鸡产蛋性能的效果观察

选择30周龄罗曼商品蛋鸡180只进行试验,研究在基础日粮中添加不同用量柠檬酸制剂,以观察其对产蛋高峰期蛋鸡产蛋性能的效果。结果表明:添加0.15%和0.20%柠檬酸组的产蛋率比对照组差异显著(p<0.05);添加0.15%和0.20%柠檬酸组的平均蛋重、料蛋比和蛋壳厚度指标比对照组和添加0.10%柠檬酸组有显著差异(p<0.05);各试验指标在添加0.10%柠檬酸组与对照组及添加0.15%和0.20%柠檬酸组之间均未达显著水平(p>0.05)。     

肉鸭速肥技术

从秋末冬初开始培育雏鸭,经过60～70d的饲养,每只鸭的体重可达2～3kg,料肉比为2.5～3.现将肉鸭速肥技术做一简单介绍. 1.精选雏鸭 选择耐寒性强,生长发育快,屠宰率高的肉鸭品种,如瘤头鸭、北京鸭、樱桃谷鸭和上海白鸭等.要求雏鸭出壳正常,绒毛光亮且覆盖肚脐,腹部柔软有弹性,肛门清洁,腿粗,嘴大,眼有神,活泼健壮有力.     

一起骡鸭传染性浆膜炎与大肠杆菌病混合感染的诊治

<正>骡鸭具有生长速度快、瘦肉率高及肥肝性能好等优良特点,但初春与初冬时节,其雏鸭成活率较低,其重要原因之一是传染性浆膜炎与大肠杆菌病混合感染致死。鸭传染性浆膜炎是由鸭疫里默氏菌引起的一种高致病性、接触性传染病,一旦发病成片流行,很难扑灭并持续存在;同时,交叉     

玉米蛋白饲料对饲养猪生长发育及养分表现消化率的影响

实验研究猪饲料中添加不同水平的玉米蛋白饲料对猪生长性能与养分表现消化率的影响,将24头猪随机分为3组,对照组仅饲喂基础饲料,实验组饲粮为玉米蛋白饲料,实验1组和实验2组替代玉米比例分别为15%和30%,实验周期30 d。表明15%玉米蛋白饲料替代组日增重较对照组显著提高18.4%,15%玉米蛋白饲料替代组料重比较对照组显著降低8.3%,与30%玉米蛋白饲料组代替相比降低11.11%。实验1组与对照组粗蛋白质消化率无显著差异,实验2组比实验1组显著下降,实验2组粗脂肪消化较对照组显著降低3.6%,日粮中添加15%玉米蛋白饲料对杂交猪采食量有促进作用,过高比例影响育肥猪的生长速度,降低对粗蛋白质的表现消化率。     

凹凸棒石可替代抗生素防控仔猪腹泻

<正>中国农业科学院北京畜牧兽医研究所张军民研究员带领科研团队,通过在不含抗生素的饲粮中添加不同水平的高纯凹凸棒石,研究发现,与不含抗生素饲粮组相比,凹凸棒石组仔猪料重比和腹泻率显著下降;同时,饲粮中添加凹凸棒石显著降低了仔猪血清中内毒素含量、二胺氧化酶活性,增加了肠绒毛表面积,增强了空肠对外界抗原及有害因子的防御功能。     

饲料中添加油脂对肉鸭生产性能的影响

本试验选用1日龄樱桃谷肉鸭500只,随机分为10个组(9个试验组和1个对照组),每组50只肉仔鸭。试验组采用二因素、每个因素三个水平的完全随机设计,即在饲粮中添加3%、6%、和9%的大豆油,每个比例分别添饲1周、2周、3周,旨在研究日粮中添加大豆油的用量和时间对肉鸭生产性能的影响。结果表明:各试验组之间以及各试验组与对照组之间肉鸭的死亡率无显著差异(P>0.05);各试验组与对照组之间肉鸭的饲料转化率有显著差异(P<0.05),各试验组之间肉鸭的饲料转化率无显著差异(P>0.05);添加大豆油的比例、时期及比例与添饲时的互作对肉鸭的日增重均有极显著的影响(P<0.01),而以添加6%的比例添饲两周的效果最好。     

Influences of dietary fatty acid profile on growth, body composition and blood chemistry in juvenile fat cod (Hexagrammos otakii Jordan et Starks)

This study was conducted to investigate the influence of dietary lipid source and n‐3 highly unsaturated fatty acids (n‐3 HUFA) level on growth, body composition and blood chemistry of juvenile fat cod. Triplicate groups of fish (13.2 ± 0.54 g) were fed the diets containing different n‐3 HUFA levels (0–30 g kg^?1) adjusted by either lauric acid or different proportions of corn oil, linseed oil and squid liver oil at 100 g kg^?1 of total lipid level. Survival was not affected by dietary fatty acids composition. Weight gain, feed efficiency and protein efficiency ratio (PER) of fish fed the diets containing squid liver oil were significantly (P < 0.05) higher than those fed the diets containing lauric acid, corn oil or linseed oil as the sole lipid source. Weight gain, feed efficiency and PER of fish increased with increasing dietary n‐3 HUFA level up to 12–16 g kg^?1, but the values decreased in fish fed the diet containing 30 g kg^?1 n‐3 HUFA. The result of second‐order polynomial regression showed that the maximum weight gain and feed efficiency could be attained at 17 g kg^?1 n‐3 HUFA. Plasma protein, glucose and cholesterol contents were not affected by dietary fatty acids composition. However, plasma triglyceride content in fish fed the diet containing lauric acid as the sole lipid source was significantly (P < 0.05) lower than that of fish fed the other diets. Lipid content of fish fed the diets containing each of lauric acid or corn oil was lower than that of fish fed the diets containing linseed oil or squid liver oil only. Fatty acid composition of polar and neutral lipid fractions in the whole body of fat cod fed the diets containing various levels of n‐3 HUFA were reflected by dietary fatty acids compositions. The contents of n‐3 HUFA in polar and neutral lipids of fish increased with an increase in dietary n‐3 HUFA level. These results indicate that dietary n‐3 HUFA are essential and the diet containing 12–17 g kg^?1 n‐3 HUFA is optimal for growth and efficient feed utilization of juvenile fat cod, however, excessive n‐3 HUFA supplement may impair the growth of fish.     

Effects of six alternative lipid sources on growth and tissue fatty acid composition in Japanese sea bass (Lateolabrax japonicus)

Ten-week experiment was carried out on Japanese sea bass (5.87 ± 0.02 g) to study the effects of replacement of fish oil with six alternative lipid sources: pork lard, PL; beef tallow, BT; poultry fat, PF; soybean oil, SO; corn oil, CO; and a mixed-fat (MF: tallow, 60%; soy oil, 20%; fish oil, 20%) on growth performance and fatty acid (FA) composition in fillet and liver. Seven isoenergetic and isonitrogenous experimental diets were formulated, containing 10% of added lipid. Fish oil was used in control diet, which was substituted by 50% with the alternative lipid sources in the other six diets.

Weight gain (WG), specific growth rate (SGR), Feed conversion ratio (FCR) feed intake and hepatosomatic index (HSI) of fish fed the experimental diets were not significantly different (P > 0.05). Protein efficiency ratio (PER) in fish fed the PF diet were significantly lower than those of fish fed SO and CO diets. Significant differences in carcass moisture and lipid contents of carcass and liver were observed among fish fed the dietary treatments. Generally, the fatty acid composition of fish fillets and livers reflected the dietary FA composition.     

饲料中添加不同含量脂肪对俄罗斯鲟（Acipenser greldenstedti Brandt）稚鱼生长的影响

本文对饲料中添加不同含量的脂肪对俄罗斯鲟（Acipenser gueldenstaedti Brandt)稚鱼生长的影响作了初步探讨，并找到了脂肪的最适添加量。试验是在专用鲟鱼苗种培育池内进行，利用黑龙江水产研究所生产的鲟鱼饲料原粉，加入猪油和豆油，比例为1：1，作为饲料中脂肪的添加。试验设0、2%、5%、8%四个梯度，试验共进行35d。实验结果表明，脂肪添加含量为5%时，其相对增重率为299.24%，饲料系数为1.28,达实验期内效果达到最佳.实验发现,俄罗斯鲟对添加猪油和豆油的饲料抢食凶猛,远远高于不添加脂肪的饲料,说明饲料添加的油脂具有一定的诱食作用.     

Evaluation of Corn Gluten Feed as a Dietary Ingredient for Pond-Raised Channel Catfish Ictalurus punctatus

Abstract.— This study was conducted to evaluate corn gluten feed as an alternative feedstuff in the diet of pond-raised channel catfish Ictalurus punctatus . Three 32%-protein diets containing 0%, 25%, or 50% corn gluten feed were tested. Channel catfish fingerlings (average weight: 57 g/fish) were stocked into 15 0.04-ha ponds at a rate of 18,530 fish/ha. Five ponds were used for each dietary treatment. Fish were fed to satiation once daily for a 147-d growing period. No differences were observed in feed consumption, weight gain, feed conversion ratio, survival, or fillet protein concentration among fish fed the test diets. Fish fed diets containing 25% and 50% corn gluten feed exhibited a lower level of visceral fat and a higher carcass yield than fish fed the control diet without corn gluten feed. The diet containing 50% corn gluten feed resulted in a lower level of fillet fat and a higher level of moisture than the control diet. There were no visible differences in the coloration of skin or fillet of channel catfish fed diets with and without corn gluten feed. Results from this study indicated that channel catfish can efficiently utilize corn gluten feed at levels up to 50%n without adverse effect on feed palatability, weight gain, or feed efficiency. Corn gluten feed may be beneficial in reducing fattiness of channel catfish and improving carcass yield by reducing the digestible energy to protein ratio of the diet.     

Effects of dietary oxidized oil and vitamin E on the growth,blood parameters and body composition of juvenile Atlantic cod Gadus morhua (Linnaeus 1758)

The effects of oxidized dietary lipid and the role of vitamin E on the growth performance, blood parameters and body composition of juvenile Atlantic cod (Gadus morhua) were evaluated over a 9‐week feeding period. Four isonitrogenous experimental diets containing fresh or oxidized fish oil with or without added vitamin E (α‐tocopherol or mixed tocopherols) were fed to juvenile cod. The oxidized lipid used had a peroxide value of 94 mEq kg^?1 oil. No significant (P>0.05) differences in growth performance (weight gain and specific growth rate) or feed utilization (feed consumption and feed efficiency ratio) were observed when oxidized dietary lipid was used. The hepatosomatic index (HSI), viscerosomatic index (VSI) and haematocrit did not show any significant (P>0.05) differences among the treatments. However, erythrocyte osmotic fragility (EOF), referred to as susceptibility to haemolysis, of fish fed oxidized oil without added vitamin E was high in comparison with those fed unoxidized oil. Supplementation with α‐tocopherol appeared to decrease haemolysis, but mixed tocopherols had no significant (P>0.05) effect on EOF. The proximate composition of fish whole body was also affected by diet treatment. Fatty acid composition of liver total lipid reflected that of dietary lipid. Variations in tissue (liver and muscle) fatty acid composition among the treatments followed the same trend as those of the dietary fatty acids. Fish fed fresh oil had a higher proportion of polyunsaturated fatty acids (PUFA) in muscle and liver lipid than those fed oxidized oil. The results suggest that oxidized dietary oil affected juvenile Atlantic cod in certain tissues and that these effects could be alleviated by supplementation of sufficient amounts of vitamin E in the diet.     

Fasting and refeeding lead to more efficient growth in lean pacu (Piaractus mesopotamicus)

We evaluated whether body fat content affects the energetic metabolism and growth in pacu submitted to daily feeding, fasting and refeeding. For 15 days, fish were fed different diets to obtain lean and fat conditions, and then subjected, for 20 days to: (1) continuously feeding (control), or (2) fasting for 15 days and refeeding for 5 days. Blood (glucose, triglycerides, cholesterol, non‐esterified fatty acids and total protein) and tissue (liver lipid and glycogen, muscle lipid and mesenteric fat) metabolic indicators, and growth performance parameters (weight gain, specific growth rate, daily feed intake and feed conversion ratio) were measured. Fasting led both lean and fat pacu to make notable use of their energy reserves, through glycogenolysis and lipolysis, reflected in reduced blood glucose and triglycerides, liver glycogen and muscle lipid levels. Lipolysis was confirmed by the high levels of non‐esterified fatty acids, especially in fat pacu. Refeeding led to higher plasma glucose and liver lipid in lean fish. Muscle fat increased in fat fish but was not restored in lean fish, while mesenteric fat index (MFI) remained the same in fat fish and increased in lean fish. Although refeeding occurred only for 5 days, lean fish grew more and were more efficient at utilizing food (higher weight gain and better feed conversion ratio). In conclusion, our results suggest that fat pacu have higher glycogenic and lipogenic abilities, and the higher deposition of lipids in fish does not mean higher availability of energy for growth when compensatory growth is stimulated by refeeding after fasting.     

Alternative vegetable lipid sources in diets for grouper, Epinephelus coioides (Hamilton): effects on growth, and muscle and liver fatty acid composition

The aim of this study was to investigate the effects of different oils on growth performance and lipid metabolism of the grouper, Epinephelus coioides. Five experimental fish meal‐based isonitrogenous and isolipidic diets were formulated containing either 5.5%‐added fish oil (FO), soybean oil (SBO), corn oil (CO), sunflower oil (SFO) or peanut oil (PO). Each diet was fed to triplicate groups of 20 fish (initial body weight 13.2±0.02 g) grown in seawater at 28.0–30.5 °C for 8 weeks. Fish were fed twice a day to visual satiety. No significant differences in the survival, weight gain, specific growth rate, feed conversion ratio, protein efficiency ratio or hepatosomatic index were found between fish fed the FO or vegetable oils (VO) diets. Dietary lipid sources did not affect whole‐body composition among grouper fed the various diets. Muscle of fish fed the FO diet had significantly higher levels of 14:0, 16:0, 16:1n‐7, 20:5n‐3[eicosapentaenoic acid (EPA)] and docosahexaenoic acid (DHA)+EPA (except for PO fed fish) compared with those of fish fed VO diets. However, the levels of 18:1n‐9, 18:2n‐6 and DHA/EPA ratios in the muscle of fish fed FO diet were significantly lower than those of fish fed the VO diets. The liver of fish fed the FO diet had significantly higher levels of 18:0, 20:5n‐3, 22:6n‐3, n‐3 highly unsaturated fatty acids and DHA+EPA than those of fish fed the VO diets, whereas increases in 18:1n‐9, 18:2n‐6 and mono‐unsaturated fatty acid levels were observed in the liver of fish fed the VO diets.     

Effects of dietary protein, and fat level and rapeseed oil on growth and tissue fatty acid composition and metabolism in Atlantic salmon (Salmo salar L.) reared at low water temperatures

A 12‐week feeding trial was conducted to elucidate the interactive effects of dietary fat, protein contents and oil source on growth, whole body proximate composition, protein productive value (PPV) and fatty acid (FA) composition of muscle and liver in Atlantic salmon (Salmo salar L.)` at low water temperatures (4.2 °C). Triplicate groups of Atlantic salmon (initial weight 1168 g) were fed six isoenergetic diets, formulated to provide either 390 g kg⁻¹ protein and 320 g kg⁻¹ fat (high‐protein diets) or 340 g kg⁻¹ protein and 360 g kg⁻¹ fat (low‐protein diets). Within each dietary protein/fat level, crude rapeseed oil (RO) comprised 0, 30 or 60% (R0, R30, R60, respectively) of the added oil. After 12 weeks, the overall growth and feed conversion ratio (FCR) were very good for all treatments [thermal growth coefficient (TGC): 4.76 (±0.23); FCR: 0.85 (±0.02)]. Significant effects were shown owing to the oil source on specific growth rate and TGC only. The liver and muscle FA compositions were highly affected by the graded inclusion of RO. The PPV was significantly affected by the dietary protein level. The results of this study suggest that more sustainable, lower protein diets with moderate RO inclusion can be used in Atlantic salmon culture at low water temperatures with no negative effects on growth and feed conversion, no major detrimental effects on lipid and FA metabolism and a positive effect on protein sparing.     

Effects of dietary lipid and environmental salinity on growth,body composition,and cold tolerance of juvenile red drum (Sciaenops ocellatus)

Simultaneous, 6-week feeding trials were conducted in which diets containing menhaden, corn, coconut and hydrogenated menhaden oil at 7.0%, plus a diet containing 14% menhaden oil, were fed to triplicate groups of juvenile red drum (Sciaenops ocellatus) at two different salinities (5 and 32%.). Weight gain was significantly (p < 0.05) affected by diet and salinity. Fish fed the diet containing 14% menhaden oil had the greatest weight gain; whereas, fish fed the diet containing coconut oil gained the least weight. Fish in brackish water had significantly greater weight gain than fish in full-strength seawater over the 6-week period, although fish fed coconut and saturated menhaden oil in brackish water had reduced survival. Dietary lipid also significantly affected muscle and liver total lipid, hepatosomatic index (HSI), and intraperitoneal fat (IPF) ratio, as fish fed the diets containing 14% menhaden oil had higher values for all of these body condition indices.After the feeding trial, fish were subjected to a chronic cold tolerance assay. In the chronic trial, where temperature was gradually reduced over a 3-week period, fish fed the diets containing menhaden oil had significantly lower median lethal temperatures (MLT) than those fish fed the diets containing coconut, corn and saturated menhaden oils. No significant effects of cold exposure were observed on muscle and liver total lipid. Cold exposure prompted a modification in lipid metabolism by lowering total saturated fatty acids and raising (n – 3) highly unsaturated fatty acids (HUFA) in the neutral lipid of liver. Fish with the lowest MLT in the chronic assay exhibited signs of conserving (n – 3) HUFA and depleting (n – 6) fatty acids [primarily 18:2 (n – 6)], resulting in higher (n – 3)/(n – 6) ratios in the polar lipid of liver. These data suggest that the lower lethal temperature of juvenile red drum can be reduced through dietary manipulation involving the inclusion of high levels of dietary lipid rich in (n – 3) HUFA.     

Evaluation of crude palm oil and refined palm olein as dietary lipids in pelleted feeds for a tropical bagrid catfish Mystus nemurus (Cuvier & Valenciennes)

The effects of different dietary lipids on the growth, feed utilization and tissue fatty acid composition of a tropical bagrid catfish Mystus nemurus (Cuvier & Valenciennes) were investigated. Eight isonitrogenous and isoenergetic semi‐purified diets were fed to triplicate groups of M. nemurus fingerlings for 10 weeks. Diet lipid levels were fixed at 10%, with 1% coming from residual oil in fishmeal and the remainder from cod liver oil (CLO), corn oil (CORN), soybean oil (SBO), crude palm oil (CPO), refined, bleached and deodorized palm olein (RBDPO) or various combinations of these oils. Catfish fed diets supplemented with 9% RBDPO showed significantly (P < 0.05) higher growth rates compared with fish fed the other seven diets. No significant differences in growth performance or feed efficiency ratio were observed between M. nemurus fed 9% CLO, CORN or CPO or fish fed diets containing 4% CLO with either 5% CORN, SBO, CPO or RBDPO. Based upon these results, palm oil‐based diets can be used effectively for M. nemurus without compromising growth or feed utilization efficiency. Muscle and liver fatty acid composition of M. nemurus reflected that of the dietary oils added in pelleted diets fed to the fish. Considering the lower cost and availability of palm oil (compared with imported vegetable oils and fish oils) in many tropical countries, its use in dietary formulations for M. nemurus, and possibly other catfish species, will make these fish feeds less expensive.